12. Figure below shows the energy levels for a hydrogen atom. (a) Calculate the ionization energy for the atom.
(b) Calculate the frequency of the spectrum due to transition from n = 4 to n= 3.
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To do work, this truck uses energy stored in chemical fuel and an electrical battery. how much total energy does this truck put out?

Which subatomic particle has a negative charge

Under the action of a constant force an object accelerates at 7.8 m/s2. what will the acceleration be if (a) the force is halved? (b) the object's mass is halved? (c) the force and the object's mass are both halved? (d) the force is halved and the object's mass is doubled?